Fluid flow control apparatus



Oct. 1, 1963 P. T. w. CHISHOLM FLUID FLOW CONTROL APPARATUS 2Sheets-Sheet 1 Filed Dec. 3, 1959 INVENTOR. PAT 7: W. CH/SHOLM BY FIG.

O 1963 P. T. w. CHISHOLM 3,105,553

FLUID FLOW CONTROL APPARATUS 2 Sheets-Sheet 2 Filed D80- 5, 1959INVENTOR. P47 7.' W. CH/SHOLM mm $51M United States Patent 3,105,553Film FLOW CDNTRQL APPARATUS Pat T. W. hishoim, Duncan, Shim, assignor toHalliburton ilompany, a corporation of Delaware Filed Dec. 3, E59, Ser.No. 857,038 7 Claims. (Cl. 16133) This invention relates to fluid flowcontrol apparatus useful in oil and gas wells or the like, such as inconnection with the performance of certain well formation testing orother operations wherein it is desired to control fluid flow at a remotelocation, which may be at a considerable depth below the surface of theground.

The invention may advantageously be applied to a bypass valvearrangement for use in lowering a string of equipment into a well, thebypass valve permitting fluid present in the well to pass upwardlyinside a portion of the string and thence through a by-pass port intothe annular space between the string and surrounding well bore. Such anarrangement alleviates to some extent the tendency of the string to befloated into the well and, also, facilitates moving the string throughany tight places which maybe encountered.

A number of by-pass valve arrangements have heretofore been employed forthe above purpose, but the operation thereof has commonly involvedeither rotation or other undesirable movement of the parts. it isparticularly desirable, when moving through a tight spot, that theby-pass valve not be of the type which is actuated either by rotation orby movement of lugs in J-slots, since it may be necessary to force theequipment by applying torque and/or raising and lowering the string,which may cause the by-pass to be inadvertently closed.

The present invention provides particular advantages when applied tofluid flow control apparatus including a by-pass valve arrangement foruse in connection with the performance of a well formation testingoperation involving the making of what is known as a dual closed-inpressure test. In making such a test it is common practice to lower orrun into the well an assembly which includes a testing tool togetherwith a Well packer assembly for isolating the formation to be tested. Ascommonly employed, the packer has an outside diameter which is verylittle smaller than the bore of the well, with the result that thepassage of fluid around the packer is considerably restricted during thelowering thereof into the well. Accordingly, the string desirably alsoincludes a by-pass valve which remains open during the lowering of thestring and which allows fluid present in the Well to flow upwardlyinside the lower portion of the string and thence out of the stringthrough a by-pass port located above the packer but below the testingtool.

After the packer assembly has reached the desired location in the welland the formation to be tested has been isolated thereby, the testervalve is then opened and, at or prior to this time, the bypass valveshould be closed.

While the tester valve is open, fluid from the isolated formation isconducted through the tester valve into a chamber provided therefor inthe testing tool. After passage of a period of time, the tester valve isclosed, whereupon the formation pressure builds up therebelow due to theproduced fluid being confined. Then the tester valve is re-opened, againallowing fluid from the formation to pass into the chamber of thetesting tool. After passage of another period of time, the tester valveis again closed, whereupon the packer is unseated and the string maythen be withdrawn from the well.

In order to facilitate the withdrawal of the string from the Well, theby-pass valve should be open but, as will be appreciated by thoseskilled in the art, the bypass valve should remain closed during theentire period retesting tool.

quired to make the dual closed-in pressure test, as aforesaid.

Thus, it is desirable for the bypass valve to be open at certain timesand to be closed at other times and, also, it is desirable for thetester valve to "be alternately opened and closed more than once whilethe by-pass valve remains closed. And yet, as previously indicated, itis desirable for the operation of the hy-pass valve not to involveeither rotation of parts or the movement of lugs in J-slots.

Accordingly, a specific object of the present invention is to provide animproved by-pass valve arrangement particularly suited for use in a wellformation testing operation wherein a dual closed-in pressure test ismade.

Another specific object of the invention is to provide an improvedby-pass valve arrangement for use with a well formation testing tool,including provision whereby the by-pass valve remains open untildesirably closed by positive movement of the tester valve.

Another specific object of the invention is to provide an improvedby-pass valve arrangement of the type described, including provisionwhereby the bypass valve doe-s not require any movement to open or closeother than such as is normal to the operation of the tester valve.

A further specific object or" the invention is to provide an improvedby-pass valve arrangement of the type described, including provisionwhereby the by-pass valve upon closing may be kept closed while thetester valve is operated to obtain a dual closed-in pressure test.

in general, the invention involves the concept of fluid flow controlapparatus including a housing having a lateral opening or port withrespect to which a plunger member surrounded by the housing is at timesmovable to change or control the fluid flow capacity of the port. In onearrangement, the plunger member is mounted for movement in the housingfrom an initial or upward position in which the port is open to a secondor downward position in which the port is at least partially closed. Anupper surface of the plunger member is continuously exposed to thepressure of fluid in the space outside the housing, such as throughanother opening provided in the housing wall. On the other hand, a lowersurface of the plunger member is exposed through the lateral port to thepressure of fluid outside the housing, but only when such port is open.

The housing is provided with a fluid passageway which extends from alocation therein at or adjacent to the lower surface of the plungermember upwardly to a remote location, such as into a chamber provided ina testing tool connected above the housing. The arrangement is such thatfluid flow in an upwardly direction through this passageway tends toreduce the pressure of fluid acting on the lower surface of the plungermember. Since, when the lateral port is closed, fluid cannot flowthrough such port from the outside of the housing, and since the uppersurface of the plunger is nonetheless exposed to the pressure of thefluid outside the housing, as aforesaid, a pressure differential isestablished which tends to hold the plunger member in its second ordownward position within the housing.

In an arrangement for use with a testing tool employed to obtain samplesof fluid from a zone or formation in an oil or gas well or the like, anassembly including the bypass valve arrangement is connected in a stringof Well p pe which also includes the testing tool and a well packer. Apassageway extending generally lengthwise through the string ofequipment permits fluid from a zone below the well packer to flowupwardly into the well pipe above the A tester valve member is mountedfor movement in the testing tool from an initial or upward positionwherein this passageway is closed-ofi to a downward posi- A the testervalve member moves to its downward position wherein the passagewaythrough the string is open. The plunger member is then retained in itsdownward or closed position due to the pressure differential, aspreviously described. The tester valve member may then be moved from itsdownward or open position to its upward or closed position, such as inmaking a closed-in pressure test, and thereafter may 'be repeatedlymoved between such posit-ions, as desired, while the bypass port remainsclosed.

In order that the by-pass port may, if desired, be subsequentlyre-opened, the housing preferably encircles a slidably mounted mandrelwhich is connected to the string of equipment therebelow and whichcooperates with the plunger member in controlling the by-pass port. Thistarrangemeut permits the plunger member and housing to be moved upwardlytogether with respect to the mandrel to a position wherein the bypassport is open, this being accomplished by raising the upper portion ofthe string at a time when the set or expanded packer is supporting orresisting upward movement of the lower portion of the string.

The foregoing and additional and further objects and advantages of theinvention will become more apparent from the following description, whenread in conjunction with the accompanying drawing wherein similarreference characters denote similar parts in all views and wherein:

FIGURE 1 is an elevation view of a portion of a string of equipmentdisposed in a cased well bore, the string including a section of tubing,a testing tool, a bypass valve in accordance with the invention, and apacker which is shown after being set or expanded at a desired locationin the well casing.

FIGURE 2 is an enlarged half section view taken on the line 22 of FIGURE1, showing the bypass valve and lower portion of the testing tool,including the tester valve, the parts being shown in the respectivepositions occupied by them at one stage of operation, such as during thelowering of the string into the well.

FIGURES 3 to 6 inclusive are each views similar to that of FIGURE 2, butshowing the parts in the respective positions occupied by them atcertain selected later stages of operation. Referring first to FIGURE 1,a section of well tubing ll? is shown disposed in a casing 12 which iscemented in place in a bore hole 14. Attached to the lower end of thetubing ll is a testing tool 16 which in turn is attached at its lowerend to by-pass valve assembly id in accordance with the invention. Apacker assembly 2 is shown attached to the lower end of the by-passvalve assembly and is illustrated in the set position, isolating aformation 22 which is to be tested.

As shown best in FIGURES l and 2 together, the bypass valve assembly 18generally includes a housing 26, a hollow inner mandrel 28 shownattached at its lower end to the packer assembly 29, a valve plunger 30slida-bly mounted within the housing 26, and a valve plunger spring 32which normally urges the plunger 30 toward its upper or open position inthe housing 26, as shown in FIGURES 2 and 3. l

The lay-pass valve housing 26 includes an upper portion 34 and a lowerportion 36 shown interconnected by threads 38; The upper portion 34- isshown connected by welded joint 39 to the lower end of an exterior wall40 of the testing tool 16. A tube-like extension 42 of the upper portion34- is disposed within the testing tool 16 in spaced relation to thewall 49. Thus, an inner annular space 44 is provided between theextension 42 and the exterior wall it? of the testing tool l6.Passageways 46 extend generally downwardly from the inner annular space44 to the interior of the by-pass valve housing 26, permitting fluidflow therethrough. A flange 43 extends inwardly from the upper portion34 and carrier QB-typev seals 59. The flange provides on the upperportion 34 an upper surface 52 and a lower surface 54. Ports 5s (shownby dash lines) permit fluid passage from the exterior of the bypassvalve housing 26 to a chamber A located therein.

The lower portion 36 of the bypass valve housing 26 has in its interior,first, a shoulder 58 and, also, a second shoulder 61 which is located asuitable distance below the first or upper shoulder 58'.

The lower portion 36 of the bypass valve housing 25 has a lowerextension 61 which is counterbored or otherwise provided with' anenlarged inside diameter. The lower extension 61 is provided near itslower end with interior splines 62. Ports 64 are located in the lowerextension s1 at or near the upper end thereof. The ports 64- are adaptedto permit fluid flow from the interior of the bypass valve housing 26 tothe exterior thereof. The term housing member includes the housing 26 aswell as the parts 34, 42, 17 and 61 which are fixed relative thereto.

The hollow inner mandrel 28, which is connected at its lower end to thepacker assembly 20, extends upwardly within the lower extension 61 ofthe lay-pass valve housing 26. Exterior splines 66 are provided on theinner mandrel 28 and are adapted to engage the interior splines 62 onthe lower extension at. The exterior splines 66 terminate at their upperend at a downwardly facing shoulder 63 and at their lower end at anupwardly facing abutment 7%. The shoulder 68 on the inner mandrel 28 isadapted to engage a surface 72, formed by the upper end of the interiorsplines 62 on the lower extension 61, to limit the upward movement ofthe hy-pass valve housing 26 relative to the inner mandrel 28, as shownin FIG- RE 2. The abutment 70 is adapted to engage a surface 74- on thelower end of lower extension 611. to limit the downward movement of thebypass valve housing 26 relative to the inner mandrel 28, as shown inFIG- URES 36. 7

The valve plunger 3% includes a solid upper portion 76 and a hollowlower portion 78. The solid upper portion 76 has an exterior shoulder8t} thereon. The solid upper portion '76, below the exterior shoulder80, extends downwardly through the interior flange 43 provided on theupper portion 34 of the valve housing 26,

forming a slidable seal with O-type seals 56 located therein. Anexterior flange 82 provided on the valve plunger 3% is positioned belowthe interior flange 48 of the valve housing 26. The arrangement is suchthat upward movement of the valve plunger 3% is limited by the uppersurface of the exterior flange 82 contacting the lower surface 54 of theinterior flange 48. The exterior flange 82 is adapted to limit thedownward movement of the valve plunger 30 upon contacting the firstshoulder 58 located in the lower portion 36 of the valve housing 26.Sealing members 84 and 86 are located in exterior recesses provided inthe lower portion 78 of the plunger 39. These members 84 and 86 areadapted to provide a s'lidable seal with the interior surface of thebypass valve housing 26, as shown in FIGURES 2 and 3, for example. Also,the lower member 86 is adapted slidably to seal against the interiorsurface of the inner mandrel 28, as shown in FIGURES 4-6. Passageways 38extend from the interior of the lower portion 78 of the plunger 39through the upper surface of the exterior flange 82 permitting fluidflow from the interior of the valve plunger 30 into the passageways 46in the upper extension 34 ofthe bypass valve housing 26.

The valve plunger spring 32 encircles the lower tubular portion 78 ofthe valve plunger 3% and is retained thereon between a lower surface ofthe exterior flange 82 and the second shoulder 6% in the lower portion36 of the by-pass valve housing 26. v

The packer assembly 20, as shown in FIGURE 1,' is

of the hook-wall type, such as may be set or expanded by combinedrelative longitudinal and rotational movement of the parts thereof. Itis understood, however, that any of various other packer arrangementsmay be employed, if desired.

The testing tool 16 may be similar to that disclosed in U.S. LettersPatent No. 2,740,479, for Drill Stem Testing Device, granted on April 3,1956, to Harry E. Schwegman. As will presently appear more fully, theby-pass valve arrangement of the present invention provides particularadvantages when employed with a tester valve of the type disclosed inthe above Schwegman patent, wherein hydraulic fluid is metered toprovide a desirable time-delay which prevents the tester valve fromopening prematurely, such as during the course of moving or forcing thestring through tight places or during the course of applying force tocause relative movement of the parts of the packer therebelow to set orexpand the same prior to performing the actual testing operation. It isunderstood, however, that the by-pass valve arrangement of the presentinvention may also be used in conjunction with other tools than thoseshown herein.

It is believed unnecessary to describe the testing tool 16 in detailand, accordingly, reference will be made herein only to certain partsthereof which are particularly related to the operation of the by-passvalve 18.

It will be noted that the testing tool 16 includes the exterior wall 40which has been previously described as being connected at welded joint39 to the by-pass valve housing 26. Also, the testing tool 16 includesan interior sleeve 90 which extends downwardly a suitable distance fromits main body and is disposed in generally parallel spaced relation tothe wall 40. Ports 94 located in the sleeve 90 permit fluid flow fromthe space 44 into the interior of the sleeve 99. Near its lower end, thesleeve 90 carries O-type seals 96 which are adapted to form afluid-tight seal with the upper extension 42 of the housing 26 intowhich the sleeve 90 is fitted.

The testing tool 16 also includes a slidable tester valve member 24which is shown as a tube-like member mounted for upward and downwardmovement within the main body 17 of the tool 16. A partition 98 dividesthe interior of the tester valve member 24 into a lower chamber 91 andan upper chamber 93. The lower chamber 91 forms part of the previouslydescribed chamber A, while the upper chamber 93 forms part of a fluidpassageway 11 shown (see FIGURE 1) extending upwardly through the tubingto a remote location which may be at the surface of the well. O-typeseals 95 encircle the exterior of the tester valve member 24 at aboutthe same location as the partition 98. Ports 97 are located just abovethe O-type seals 95 and extend through the wall of the tester valvemember 24 into the upper chamber 93. That part of the tester valvemember 24 which is below the partition 98 carries near its lower end 99O-type seals 89 which form a slidable, yet fluid tight, seal with theinterior surface of the upper extension 42 of the valve housing 26.Between the lower end 99 of the tester valve member 24- and the O-typeseals 89, ports 92 extend through the sidewall and allow fluid passagetherethrough.

In performing a testing operation using the equipment herein described,the testing tool 16 and by-pass valve 18 are attached in theconventional manner to the lower end of the tubing 10. The packerassembly 20 is attached to the inner mandrel 28 of the by-pass valve 18.The apparatus is then run into the well casing 12 until it is located ina suitable position to perform the test.

As the apparatus enters the well, the tester valve member 24, valveplunger 36', and inner mandrel 28 are in the respective positionsillustrated in FIGURE 2. That is, the tester valve member 24 is in itsupward or closed position and the by-pass valve plunger '30 is in itsupward or open position.

During the lowering of the string, the mandrel 28 may move upwardlyrelative to the housing member to some extent and, particularly if atight place is encountered, may reach its uppermost position, as shownin FIGURE 3, prior to the string reaching the desired loca tion in thecasing 12.

The well casing 12 will ordinarily contain fluids which must bepartially displaced by the string as it is lowered into the well. Aspreviously stated, the packer assembly 20 has an outside diameter onlyslightly smaller than the inside diameter of the casing 12. The by-passvalve 18 remains open during the lowering to prevent fluids from beingtrapped below the string and severely restricting or stopping thedownward movement due to the small flow area around the packer assembly20. Thus, it will be noted in FIGURES 2 and 3 that fluid in the casing12 below the packer assembly 24 is permitted to pass upwardly throughthe interior of the assembly 20 and the by-pass valve 18 and out throughthe by-pass ports 64 of the housing 26 into the portion of the casing 12above the assembly 26.

Upon reaching the desired location, the tubing 10 is rotated and raisedor lowered, as required, to set the packer assembly 26. It will be notedthat rotation of the tubing 10 may be imparted to the upper portion ofthe packer assembly 20 through the splines 62 and 66.

After the packer assembly 29 is set, isolating the formation 22, aportion of the weight of the tubing 10 is placed through the testingtool 16 onto the by-pass housing 26 and the packer assembly 26. If forsome reason the mandrel 28 is not already in its uppermost positionwithin the housing 26, the application of this weight will first movethe other parts downward relative to the mandrel 28. Thereafter, theforce applied due to the weight of the tubing 10 will cause the testervalve member 24 to begin its downward movement. Also, the valve plunger3!) begins to move downwardly with the tester valve member 24 when thelower end 99 of the valve member 24 contacts the shoulder of the plunger30.

As described more fully in the aforesaid Schwegman Patent 2,740,479, thetesting tool 16 is preferably constructed so that the tester valvemember 24 will initially move downwardly very slowly, such as from theposition shown in FIGURE 3 to the position shown in FIGURE 4. However,due to the provision of a by-pass passageway for themetered fluid, thetester valve member 24 will thereafter move downwardly rapidly, such asfrom the position shown in FIGURE 4 to the position shown in FIGURE 5.

Since fluids in the space outside the by-pass valve 18 are at all timespermitted to pass through the ports 56 provided in the upper portion 34of the housing 26 and through the ports 92 provided in the lower endportion of the tester valve member 24, hydrostatic pressure is at alltimes present in the chamber A. Thus, a downward force due to thehydrostatic pressure in the chamber A is at all times exerted on theupper end of the valve plunger 39. However, when the by-pass ports 64are open, as shown in FIGURES 2 and 3, .an upward force, which is alsodue to hydrostatic pressure and is preferably equal approximately to theaforesaid downward force, is exerted on the lower end of the valveplunger 30. As a result, the valve plunger 30 is in a balanced conditioninsofar as fluid pressures are concerned and it is only necessary forthe tester valve member 24 to overcome the upward force of the spring 32to move the plunger 30 downwardly.

It will be noted in FIGURE 4 that the tester valve member 24 and theby-pass valve plunger 35} are shown moved downwardly a sufficientdistance so that the port 94 in the interior sleeve of the valve member24 is sealed by the seals 95 and also the by-pass ports 64 in thehousing 26 of the valve 18 are sealed by the members 84 and 86 carriedby the plunger 30. In this position, both of the valves are closed.

When the tester valve member 24 and the by-pass valve plunger 39 havemoved to their extreme downward positions, as shown in FIGURE 5, theport 94 in the sleeve 9%? is then in alignment with the port 97 in thetester valve member 24-, which is thus in its open position. However,the by-pass ports 64 remain sealed by the members 84 and 86. Thus,fluids trapped below the packer assembly 29 and in the interior of theassembly 29 are permitted or caused to fiowupwardly through the interiorof the valve plunger 39, then through the transverse passageways 8% intothe inner annular space 44, then through the aligned ports 94 and 7 intothe chamber 93 and thence into the passageway 11 which is at reducedpressure.

As the formation 22 produces fluids, which pass upwardly through theapparatus, as aforesaid, the pressure below the packer assembly 2% andvalve plunger 30 suddenly decreases to approximately atmospheric andthen gradually increases toward the normal pressure of the formation 22.Since the formation pressure is considerably less than hydrostaticpressure, the upward force exerted on the valve plunger 3i? due toformation pressure and the spring 32, is less than the downward forceexerted by the hydrostatic pressure in the chamber A and the valveplunger 30 remains in its lower or closed position, as shown in FIGURE5.

While the valve plunger 34 is thus held in its closed position, aclosed-in pressure test may be made. This is accomplished by lifting thetubing 16 a short distance upwardly, thus removing a portion of theweight exerted on the apparatus connected therebelow. The tester valvemember 24 then returns to its upper or closed position,

preventing any further upward flow of formation fluid into passageway11. However, as previously pointed out, the by-pass valve plunger 30remains in its downward or closed position.

.After the closed-in test is made, the tubing weight is again set downand the tester valve member 24 again moves downwardly into its openposition, as shown in FIGURE 5. Fluid may again flow upwardly into thepassageway 11 through the ports and passageways 83, 46, 9 and 97, ashereinbefore described.

It will be appreciated by those skilled in the art that a secondclosed-in pressure test may be made by repeating the foregoing steps.After the desired tests have been made, the by-pass valve 18 may beopened by lifting the tubing 1% until the surface 72 at the upper end ofthe interior splines 62 contacts the shoulder 68 of the inner mandrel28. When this has been accomplished, the tester valve member 24 willhave moved upwardly to its closed position and the inner surface of theinner mandrel 28 will be out of engagement with thesealing member 86 onthe by-pass valve plunger 31 Fluid at hydrostatic pressure will thenpass through the port 64 and will equalize the force exerted on thevalve plunger 30 by the fluid in the chamber A. The valve plunger 30will then be driven upwardly by the spring 32 into the upward or openposition, as shown in FIGURE 2.

The apparatus may then be removed from the well bore 14- by conventionalmeans after unseating the packer assembly 28.

From the foregoing, it will be seen that a by-pass valve constructed inaccordance with the invention provides a solution to many of theproblems encountered in testing apparatus. The embodiment hereinpresented is by way of example only and many variations thereto may bemade without departing from the spirit of the invention or the scope ofthe annexed claims.

I claim:

1. In fluid flow control apparatus, the combination of I a housingmember adapted to be connected between sections of a conduit, meansforming a passageway extending longitudinally through said housingmember whereby fluid may flow from a section of the conduit therebelowinto a section of the conduit thereabove, said housing member having aby-pass port in the wall thereof, said by-pass port being adapted whenopen to provide fluid communication (a between said passageway and theoutside of said housing member, a main valve member mounted for movementin said housing member from an initial position closing said passagewayto a position wherein said passageway is open, and a movably mountedby-pass valve member for controlling fluid flow through said bypassport, the housing member having a chamber therein defined between saidvalve members, the housing member having a port connecting said chamberto the exterior of said housing memher, said by-pass valve member beingengageable by said main valve member for movement from an initial openposition to a position closing said by-pass port when said main valvemember is moved from its initial closed position to a position whereinsaid passageway is open.

2. In a well sampling tool for use with a hollow expansible packerdevice and adapted to be lowered into a well below the fluid leveltherein, the combination of: a tubular housing member, means including ahollow mandrel for connecting the lower end of the housing member'to thehollow expansible packer device, the housing member having a by-passport permitting well fluid to pass through the hollow packer device andthrough the interior of said hollow mandrel and through the bypass portas the tool and packer are lowered into the well, a by-pass valve membermounted for axial sliding movement within the housing member forcontrolling flow through said by-pass port, the housing member having asecond port and having a passage communicating with said second port,said by-pass valve member having a passage communicating with saidhousing member passage and with the interior of said hollow mandrel,said housing member having a chamber and having a port communicatingwith the chamber and with the exterior of said housing member, the upperend of the by-pass valve member extending into said chamber and beingthereby subjected to hydraulic pressure of fluid in the well, the lowerend of the by-pass valve member being exposed to pressure of fluidwithin the hollow mandrel and below the packer device whereby uponexpansion of the packer device and movement of the by-pass valve memberto close the by-pass port, fluid under pressure of the well formationmay pass upward through the hollow mandrel and passages in the by-passvalve member and housing member through the second port.

3. -In a well sampling tool for use with a hollow expansible packerdevice and adapted to be lowered into a well below the fluid leveltherein, the combination of: a tubular housingmember, means including ahollow mandrel for connecting the lower end of the housing member to thehollow expansible packer device, the housing member having a by-passport permitting well fluid to pass through the hollow packer device andthrough the interior of said hollow mandrel and through the by-pass portas the tool and packer are lowered into the well, a bypass valve membermounted for axial sliding movement within the housing member forcontrolling flow through said by-pass port, the housing member having asecond port and having a passage communicating with said second port,said by-pass valve member having a passage communicating with saidhousing member passage and with the interior of said hollow mandrel,said housing member having a chamber and having a port communicatingwith the chamber and with the exterior of said housing member, resilientmeans in the housing member acting to hold the by-pass valve member inopen position, means in the housing member for moving the by-pass valvemember to closed position against the action of said resilient means,the upper end of the bypass valve member extending into said chamber andbeing thereby subjected to hydraulic pressure of fluid in the well, thelower end of the by-pass valve member being ex posed to pressure offluid within the hollow mandrel and below the packer device whereby uponexpansion of the packer device and movement of the by-pass valve memberto close the bypass port, fluid under pressure of the well formation maypass upward through the hollow mandrel and passages in the by-pass valvemember and housing member through the second port.

4. In a well sampling tool for use with a hollow expansible packerdevice and adapted to be lowered into a well below the fluid leveltherein, the combination of: a tubular housing member, a hollow mandrelspline-connected to the lower end of the housing member and having meansfor connection to the hollow expansible packer device, the housingmember having a by-pass port permitting well fluid to pass through thehollow packer device and through the interior of said hollow mandrel andthrough the by-pass port as the tool and packer are lowered into thewell, a by-pass valve member mounted for axial sliding movement withinthe housing member for controlling flow through said by-pass port, thehousing member having a second port and having a passage communicatingwith said second port, said by-pass valve member having a passagecommunicating with said housing member passage and with the interior ofsaid hollow mandrel, said housing member having a chamber and having aport communicating with the chamber and with the exterior of saidhousing member, the upper end of the by-pass valve member extending intosaid chamber and being thereby subjected to hydraulic pressure of fluidin the well, the lower end of the by-pass valve member being exposed topressure of fluid within the hollow mandrel and below the packer device.

5. A well tool comprising, in combination: a tubular housing memberhaving an axial bore and having means forming a restricted opening atthe upper end of said axial bore, the housing member having a firstchamber therein above said restricted opening and having a secondchamber therein below said restricted opening, a hollow mandrel having aspline connection to the lower end of the housing member and havingmeans for connection to a packer assembly, a by-pass valve memberslidably mounted in said axial bore and having a portion forming asliding seal within said restricted opening, said by-pass valve memberalso having a passage communicating with the said second chamber andwith the interior of said hollow mandrel, bias means in the housingmember arranged to apply an upward force against said by-pass valvemember, means forming a by-pass port in the lower portion of the housingmember communicating with the interior of the hollow mandrel, a lowerportion of said by-pass valve member being movable into sealingrelationship with the interior of the hollow mandrel to prevent fiowthrough said by-pass port, an upper portion of said by-pass valve memberextending into said first chamber, port means establishing communicationbetween said first chamber and the exterior of said housing member, andmeans within said housing member to move said by-pass valve memberagainst the force of said bias means into sealing relationship withinsaid hollow mandrel.

6. A well tool comprising, in combination: a tubular housing memberhaving an upper axial bore and having means forming a restricted openingat the lower end of said bore, the housing member having a first portcommunicating with said upper bore and having a passage connecting saidfirst port with a first chamber within the interior of the housingmember below said restricted opening, a tester valve member slidablymounted in said upper bore and having an inlet port for registry withsaid first port, a by-pass valve member slidably mounted in said lowerbore and having a portion forming a sliding seal within said restrictedopening, said by-pass valve member also having a passage communicatingwith the said first chamber and with the interior of the lower portionof said housing member, bias means in said housing member arranged toapply an upward force against said by-pass valve member, means formingby-pass port in the lower portion of the tubular housing member, saidby-pass valve member being movable downward against the force of saidbias means to prevent flow through said by-pass port, said valve membersand said upper bore defining a second chamber within said housing memberabove said restricted opening, the upper portion of said by-pass valvemember extending into said second chamber, port means establishingcommunication between said second chamber and the exterior of saidhousing member, and means whereby downward movement of said tester valvemember to align said inlet port and said first port serves to move saidby-pass valve member downward to prevent flow through said by-pass port.

7. A well tool comprising, in combination: a tubular housing memberhaving upper and lower axial bores and having means forming a restrictedopening between said bores, the housing member having a first portcommunicating with said upper bore and having a passage connecting saidfirst port with a first chamber within the interior of the housingmember below said restricted opening, a hollow mandrel having a splineconnection to the lower end of the housing member and having means forconnection to a packer assembly, a tester valve member slidably mountedin said upper bore and having an inlet port for registry with said firstport, a by-pass valve member slidably mounted in said lower bore andhaving a portion forming a sliding seal within said restricted opening,said by-pass valve member also having a passage communicating with thesaid first chamber and with the interior of said hollow mandrel, aspring in the housing member arranged to apply an upward force againstsaid by-pass valve member, means forming a by-pass port in the lowerportion of the housing member communicating with the interior of thehollow mandrel, a portion of said by-pass valve member being movableinto sealing relationship with the interior of the hollow mandrel toprevent flow through said by-pass port, said valve members and saidupper bore defining a second chamber within said housing member abovesaid restricted opening, the upper portion of said by-pass valve memberextending into said second chamber, port means establishingcommunication between said second chamber and the exterior of saidhousing member, and means whereby downward movement of said tester valvemember to align said inlet port and said first port serves to move saidby-pass valve member against the force of said spring into sealingrelationship within said hollow mandrel.

References Cited in the file of this patent UNITED STATES PATENTS2,332,144 Hanes Oct. 19, 1943 2,740,479 Schwegman Apr. 3, 1956 2,901,001Nutter Aug. 25, 1959

1. IN FLUID FLOW CONTROL APPARATUS, THE COMBINATION OF A HOUSING MEMBERADAPTED TO BE CONNECTED BETWEEN SECTIONS OF A CONDUIT, MEANS FORMING APASSAGEWAY EXTENDING LONGITAUDINALLY THROUGH SAID HOUSING MEMBER WHEREBYFLUID MAY FLOW FROM A SECTION OF THE CONDUIT THEREBELOW INTO A SECTIONOF THE CONDUIT THEREABOVE, SAID HOUSING MEMBER HAVING A BY-PASS PORT INTHE WALL THEREOF, SAID BY-PASS PORT BEING ADAPTED WHEN OPEN TO PROVIDEFLUID COMMUNICATION BETWEEN SAID PASSAGEWAY AND THE OUTSIDE OF SAIDHOUSING MEMBER, A MAIN VALVE MEMBER MOUNTED FOR MOVEMENT IN SAID HOUSINGMEMBER FROM AN INITIAL POSITION CLOSING SAID PASSAGEWAY TO A POSITIONWHEREIN SAID PASSAGEWAY IS OPEN, AND A MOVABLY MOUNTED BY-PASS VALVEMEMBER FOR CON-